# Fault Current Calculator vs Mike Holt's Electrical Toolbox

The clearest difference is review sentiment: Mike Holt's Electrical Toolbox at 77% against Fault Current Calculator's 0%. Mike Holt's Electrical Toolbox also leads on rating (4.6 vs 3.1) and in-app purchases (none vs 2). On price, update cadence, ads and device support there is nothing between them.

Both are free to download. Fault Current Calculator sells 2 in-app purchases, starting at $4.99 per month. Mike Holt's Electrical Toolbox asks for nothing beyond the download.

Mike Holt's Electrical Toolbox holds the better App Store score, 4.6 against 3.1. That said, the two scores are not equally well evidenced: Mike Holt's Electrical Toolbox has 197 ratings behind it against 23, so its average is the more settled of the two. Written reviews point the same way: 0% of Fault Current Calculator's written reviews are positive against 77% of Mike Holt's Electrical Toolbox's.

Fault Current Calculator ships an update every 4 months, Mike Holt's Electrical Toolbox every 3 months. The most recent releases landed on August 20, 2026 and September 21, 2026 respectively.

## The numbers

| Metric | Fault Current Calculator | Mike Holt's Electrical Toolbox |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [3.1 (23 ratings)](https://appshunter.io/ios/app/fault-current-calculator/id647477910/reviews) | **[4.6 (197 ratings)](https://appshunter.io/ios/app/mike-holts-electrical-toolbox/id1406630647/reviews)** |
| Number of ratings | 23 | **197** |
| Positive reviews | 0.0% of reviews | **76.7% of reviews** |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 3 months** |
| Monetization | Freemium | **Free** |
| Size | 25 MB | 26 MB |
| Requires iOS | 14.0 | 14.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 17+ | 4+ |
| Developer | [Cooper Bussmann, LLC](https://appshunter.io/developer/609315535) | [Mike Holt Enterprises](https://appshunter.io/developer/1349960186) |

## What reviewers say

### Fault Current Calculator

[App page](https://appshunter.io/ios/app/fault-current-calculator/id647477910)

This tool helps contractors, engineers, and electricians quickly calculate available fault current on single and three-phase electrical systems. It also assists in sizing fuses and conductors for various circuits and can generate labels for service equipment.

**Highlights:** Calculate available fault current, Size fuses and conductors, Generate service equipment labels, Single and three-phase system support, NEC® 110.24 compliance

**Features:** macOS Compatibility

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Monthly Subscription | $4.99 | per month |
| Pro Annual Subscription | $39.99 | per year |


### Mike Holt's Electrical Toolbox

[App page](https://appshunter.io/ios/app/mike-holts-electrical-toolbox/id1406630647)

This app provides essential calculations for electricians, inspectors, contractors, and engineers. It helps determine conductor sizing, circuit protection, race sizing, and grounding conductor sizes for various electrical equipment and services.

**Highlights:** Conductor sizing, Voltage drop limitations, Circuit protection sizing, Race sizing, Equipment grounding conductor sizing, Dwelling-unit service calculations

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases:** none

**What reviewers like**

- 👍 Great app for electricians
- 💡 Provides code article references
- 👍 Useful for on-the-spot reference
- 👍 Excellent for verifying calculations
- 👍 Helpful for exam preparation

**What reviewers complain about**

- 🐛 Emailing results not working
- 🐛 Outdated information
- 🐛 Load calc a little clunky
- 🐛 Content setup needs overhaul
- 🐛 Video series lacks completion system

**Reported bugs**

- Cannot email results
- Video player widescreen exit bug
- Previous calculation data not erased
- App content is outdated

**Requested features**

- Increase transformer capacity to 225kva
- Add option to print load calc
- Update to NEC 2020
- Add completion system for video series
- Refine user interface for better usability


## Frequently asked questions

### Is Fault Current Calculator free?

Fault Current Calculator is free to download, with in-app purchases available.

### Is Mike Holt's Electrical Toolbox free?

Mike Holt's Electrical Toolbox is free to download, with no in-app purchases.

### Which has better reviews, Fault Current Calculator or Mike Holt's Electrical Toolbox?

Mike Holt's Electrical Toolbox is rated higher. Fault Current Calculator averages 3.1 out of 5 from 23 ratings, while Mike Holt's Electrical Toolbox averages 4.6 from 197 ratings.

### Do Fault Current Calculator or Mike Holt's Electrical Toolbox have ads?

Neither Fault Current Calculator nor Mike Holt's Electrical Toolbox shows ads.

### Which is updated more often, Fault Current Calculator or Mike Holt's Electrical Toolbox?

Fault Current Calculator ships an update every 4 months, and Mike Holt's Electrical Toolbox every 3 months. Most recently, Fault Current Calculator was updated on August 20, 2026 and Mike Holt's Electrical Toolbox on September 21, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*